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I'm an apprentice electrician, as far as I know, grounding is sending the charge to the ground. Isn't this impossible in a car, considering there arn't conductors touching the actual ground? Does the charge getting absorbed by the rubber in the tires count as grounding? If so, what wire on my cigarette lighter do I use to tap splice and ground. I have an '03 Civic SI, I was told it was possibly the black wire.

 
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The traditional grounding colour is black, so ususally people refer it to as the black wire. Grounding doesnt really ground to the floor but through the body/frame to and back into the battery. If you look on the negative side of the battery, there are grounds that connect to the frame, meaning the body of the car would be a ground too.

 
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Ah, in electricity the ground wire is usualy bare, or green. Are you saying that for the cigarette lighter, the black wire is 100% the ground, is there any way I can make sure?

 
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no im not 100% sure, but you can check with a voltmeter. Just find a 12v source and connect one side to a wire. Check if there is a voltage difference.

 
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that's in AC, not DC. in AC you have hot, neutral and ground (assuming a 1-phase system). in DC you just have positive and ground/negative. on cars, the grounds can be many different colors. go buy a Hayne's repair manual is the best thing to do. that way, no matter what system you're trying to work on, you'll have diagrams.

What are you connecting that you need a ground for? the reason i ask is that the wires on the power plug have a max rating and really aren't designed to support additional loads.